Both Fröbel and Unger were interested in art and Unger was educated at the Kunstakademie in Munich. They worked close together, but probably Unger had to follow Fröbel's instructions. Unger must have been the most competent to know about the elements of art you can find in "Mutter- und Koselieder". However, there are many symbols from the Ancients, Medevial and Renaissance art in "Mutter- und Koselieder".
Caroline von Holzhausen was mother of two of Fröbels private pupils.